目的研究短时间外部高温和低温环境刺激对小鼠空间记忆、体重及运动的影响。方法C57BL/6雄性小鼠24只,2~3月龄,体重21—24g,将小鼠按照随机数字表法分为3组(每组8只):对照组、高温组和低温组。3组小鼠在20℃常规饲养环境温度下适应3周后,将高温组小鼠置于38℃高温环境,低温组小鼠置于4℃低温环境,对照组置于20℃的室温环境中,环境温度刺激持续6h。采用小鼠智能鼠笼自动监测小鼠空间记忆和运动,每日记录各组小鼠体重水平变化。结果与对照组比较,高温组小鼠在处理后第3-6天出现明显的空间记忆提高[第3天(82±7)%比(74±8)%,第4天(87±12)%比(71±4)%,第5天(80±9)%比(6±+6)%,第6天(84±6)%比(73±7)%](P〈0.05),且其体重水平持续降至处理后第8天[第5天(27.5±1.2)g比(29.1±0.7)g,第6天(28.6±1.0)g比(30.1±0.7)g,第7天(28.7±1.0)g比(30.4±0.8)g.第8天(29.9±0.5)g比(30.6±0.5)g](P〈0.05)。高温及低温处理后第2-4天均表现出明显的鼻触时间减少[第2天(361±74)s比(576±88)s,第3天(487±104)S比(631±81)S,第4天(532±88)S比(678±35)S](P〈0.05)。低温组未见明显空间记忆及体重水平改变;在处理后3~4d表现为鼻触时间减少[第3天(501±103)S比(631±81)s,第4天(492±74)S比(678±35)s](P〈0.05)。结论高温环境可升高小鼠空间记忆水平,减轻体重,减少运动量,低温环境可减少运动量。
Objective To explore the effects of ambient temperature on spatial memory, weight, and activity. Methods Twenty four mice were randomly divided into three groups(n=8): hot group (38 ℃ for 6 h), cold group (4℃ for 6 h), and control group (20℃). Intellicage for mice was used to continuously test spatial memory and mice weight was measured every day. Results Compared with control group, the spatial memory of mice in hot group was significantly improved after 3-6 days' temperature treatments with comer preference increase from (74±8)% to (82±7)% at Day3, (71±4)% to (87±12)% at Day4, (67±6)% to (80±9)% at DayS, (73±7)% to (84±6)% at Day6 (P〈0.05), while body weight tarted to decrease markedly until Day 8 [Day 5 (27.5±1.2) g vs (29.1±0.7) g,Day 6 (28.6±1.0) g vs (30.1±0.7) g,Day 7 (28.7±1.0) g vs (30.4±0.8) g,Day 8 (29.9±0.5) g vs (30.6±0.5) g] (P〈0.05). Cold temperature did not affect the spatial memory and body weight of mice. Both hot group and cold group mice showed decreased gross activity 2-4 days' [Day 2 (361±74) s vs (576±88)s, Day 3 (487±104)s vs (631±81)s, Day 4 (532±88) s vs (678±35)s] (P〈0.05). Conclusions Our study showed that ambient temperature, especially hot environment, could affect the spatial memory, body weight, and activity of mice.